Synonyms and other taxonomic changes
Pterourus troilus - new name according to Minno et al, 2005
(1) Size
Wing span: 3 - 4 inches (7.5 - 10 cm).(1)
Identification
Adult: Upper surface of forewing is mostly black with ivory spots along margin. Upper surface of hindwing has orange spot on costal margin and sheen of bluish (female) or bluish-green (male) scales. Underside of hindwing with pale green marginal spots.(1) Median spotband on underside of hindwing missing one orange spot.(2)
Caterpillar: First three instars resemble a bird dropping. Last two instars are green with large eyespots - the two largest on third thoracic segment have black "pupils", two smaller ones on first abdominal segment do not. The larva changes color to orange or yellow just prior to pupating.
Range
Eastern states from southern Canada to Florida; west to Oklahoma and central Texas. Occasionally strays to North Dakota, central Colorado, and Cuba.(1)
Habitat
Deciduous woodlands, fields, roadsides, yards, pine barrens, wooded swamps, and parks.(1)
Season
2 generations per year from April-October. In Florida, several generations between March-December.(1)
Food
Caterpillar hosts: Spicebush (Lindera benzoin), Sassafras trees (Sassafras albidum), Pondspice (Litsea aestivalis) Red, Swamp and Silk Bays (Persea spp.); perhaps prickly ash (Zanthoxylum americanum), Tulip tree (Liriodendron tulipifera), Sweetbay (Magnolia virginiana), and Camphor (Cinnamomum camphora).
Adult food: Nectar from Japanese honeysuckle, jewelweed, thistles, milkweed, azalea, dogbane, lantana, mimosa, and sweet pepperbush.(1)
Life Cycle
Males patrol in woods, roads and woodland edges to find receptive females. Females lay single eggs on underside of host plant leaves. Caterpillars live in shelters of folded-over leaves and come out to feed at night. Some chrysalids from each generation hibernate.(1)
See Also
Adults are very similar to the
Black Swallowtail, but may be distinguished by missing one orange spot in the median spot-band on the hind wing (underside). Above, this species might be confused with
Pipevine Swallowtail: both have blue on the hind wing, but the latter species has fewer and smaller markings on the front wing.
Late instar larvae are similar to those of the Palamedes Swallowtail, but the underside of that species is rusty-brown or maroon beneath, this one is gray. Both have a blue spot on the first abdominal segment, which on Palamedes is adjacent to the eyespot but on Spicebush is within it.
Spicebush Swallowtail
Palamedes Swallowtail
